Method and device for positioning strips and rolls in order to connect same to an unwinding machine

ABSTRACT

A method and device for positioning strips and rolls in order to connect same to an unwinding machine. The method is characterised in that it consists in physically representing the position at which the side of the roll ( 3 ) must be positioned in relation to the longitudinal axis of the machine, on the outside diameter of the roll with the aid of a light beam emitter ( 6 ) that emits light that is visible to the operator and without the use of an active receiver. The invention is especially suitable for machines used for the continuous unwinding of strips of material and, in particular, for machines used to unwind rolls of paper or card in order to feed a downstream machine.

This invention relates to the field of continuous rolling and unrollingmachines for web materials, especially machines for unrolling paper orcardboard spools, for purposes of feeding a downstream machine, and itsobject is a process for positioning webs and spools for purposes ofconnection on an unrolling machine.

The object of the invention is likewise a device for implementing thisprocess.

To continuously feed a machine placed downstream from a machine forunrolling paper or cardboard spools, the web of a spool that is endingmust be joined to the end of a web of a new spool without the downstreammachine, which can be, for example, a printing machine, being stopped.

For this purpose, a spool in the course of unwinding is placed on one ofthe two spindles of an unrolling machine.

To accomplish joining without stopping the downstream machine, a newspool is placed on standby for a second unrolling spindle of saidunrolling machine. The start of the web of this new spool must bepositioned such that it is correctly aligned both laterally andangularly with the web that is ending.

Currently, new spools and webs are prepositioned by the operator usinggraduated scales located on the spindle that bears the spool and on thepreparation zone of the start of the web waiting to be joined. Thus,when, for example, the spool has a known width of 600 mm, the operatorwill slide the spool onto the spindle until the end of the mandrel, ofcardboard or another material, of the spool is located next to acorresponding 600 mm reference corresponding to the graduated scale ofthe spindle that bears said spool, such that the side of the core of thespool is placed as exactly as possible opposite the corresponding 600 mmreference, i.e., is aligned with this reference.

Then, the operator will unroll a sufficient length of the new web thathe will arrange opposite the 600 mm reference of the graduated scale ofthe holding zone of the start of this new web. In this way, apparentlycorrect alignment is obtained between the new spool and the unrollingmachine, and the new web will be able to unwind in the unrolling machinewithout the risk of running skewed.

However, if the new spool has a shape defect, for example when the sideat the level of the outside diameter of the spool is not verticallyplumb with the side at the level of the inside diameter, then the startof the new web can be placed, in the preparation zone of the start ofthe web, skewed relative to the longitudinal axis of the machine. Thisresults in malfunctions, especially of longitudinal folds that can causetears of the web in unwinding or can damage the main part of theproduction line.

To eliminate this type of defect, using a mechanical frame to feel theside of the spool at the level of its larger diameter in order tocorrectly position the spool on the unwinding machine is known. Thistype of device with a frame must be able to take into account a largerange of diameters and values of fabric width, which greatly complicatesconstruction and thus the cost of the unrolling machine. Moreover, theremay be risks of product deterioration, often expensive and delicate,when the feelers come into contact with the spool.

U.S. Pat. No. 6,007,017 likewise discloses a process for positioning aweb, in which the position of the web is measured by means of distancesensors, the acquired values being compared to a reference and the webbeing moved to make the acquired values coincide with the reference.This document relates to a process for automatic control requiring theuse of distance sensors that can notify a control element of theposition of the web. These distance sensors can be light wave orultrasonic transmitter-receivers.

These sensors, however, do not emit a beam of visible light allowing themarking of a position, i.e., allowing an operator to perfectly locate avertical plane in which the edge of a spool must be positioned, withoutintervention of specific control means.

Moreover, U.S. Pat. No. 5,133,511 describes a positioning processconsisting in measuring the position of a web by means of a positionsensor and a CCD camera that, depending on the number and the positionof the activated pixels of the sensor, notifies a control and adjustmentelement about the position of the web. This process uses a light sourcethat is a lamp that illuminates the zone filmed by the CCD camera and isnot suited to the marking of a position by delivering a line of light.

Finally, U.S. Pat. No. 4,131,206 also discloses a process for webpositioning in which the web is moved laterally until the light flux ofa light beam emitted by a light source and detected by a receiver isinterrupted. This process implements a photoelectric-type barrier meanswith an emission source that is not designed to mark a position on theweb, but to illuminate a receiver that notifies a control element aboutthe web position.

The object of this invention is to remedy the defects of the knownprocesses and devices by suggesting a process for positioning the websand spools for purposes of joining on an unrolling. machine and a devicefor implementing this process that allows perfect alignment between theweb that is ending and the new web and unrolling the web withoutlongitudinal folds by implementing a group of operations completelyunder the control of an operator who verifies the position, withoutusing complex and expensive complementary means for electronic and/orinformation technology control.

For this purpose, the process according to the invention ischaracterized in that it consists in marking, at the level of theoutside diameter of a spool, by means of an emitter of a beam of lightthat is visible to an operator and without using an active receiver, theposition to which the side of said spool must be positioned relative tothe longitudinal axis of the unrolling machine.

The object of the invention is likewise a device for implementing thisprocess that is characterized in that it is composed essentially of atleast one emitter of a light beam in the form of at least one linearlight beam or at least one light plane of light that is visible to anoperator, said emitter working with a passive indexing means, withoutusing an active receiver.

The invention will be better understood, thanks to the followingdescription that relates to a preferred embodiment, given by way of anonlimiting example and explained with reference to the accompanyingdiagrammatic drawings, in which:

FIG. 1 is a side elevation view of an unrolling machine that is equippedwith a device that implements the process according to the invention;

FIG. 2 is a partial perspective view of a device that implements theprocess;

FIG. 3 is a view analogous to that of FIG. 2 that represents a means ofcontrolling the alignment of the web as it unwinds relative to thelongitudinal axis of the unrolling machine, and

FIG. 4 is a view analogous to the one of FIG. 2 showing a variantembodiment of the device that implements the process.

FIG. 1 of the accompanying drawings shows a machine for unrolling paperor cardboard spools for purposes of feeding a machine placed downstreamsuch as a printing machine or the like, this machine being essentiallycomposed of a chassis 1 that supports means 2 of the spool-holder 3 thatcan move transversely to the longitudinal axis of the machine, andoptionally of a device 4 for storing the web and a group 5 forpreparation of a new web to be connected and for joining this web to aweb that is ending.

To accomplish positioning of the webs and spools for purposes of joiningon this unrolling machine, according to the invention, a process isimplemented that consists in marking, at the level of the outsidediameter of a spool 3, by means of an emitter 6 of a light beam of lightthat is visible to an operator and without using an active receiver, theposition at which the side of said spool 3 must be positioned relativeto the longitudinal axis of the unrolling machine.

To implement this process, according to the invention, there is a devicethat is composed essentially of at least one emitter 6 of a light beamin the form of at least one linear light beam or at least one lightplane of light that is visible to an operator, said emitter working witha passive indexing means 7, 71 (FIGS. 2 and 4) provided on the group 5for preparation of a new web to be connected and for joining this web toa web that is ending, without using an active receiver.

The positioning of the webs and spools for purposes of connectionconsists in loading the spool 3 onto the free spindle of a spool-holdermeans 2 to reach a corresponding reference 9 (FIGS. 2 and 4), thenoptionally to laterally position the emitter 6 relative to thelongitudinal axis of the machine, working with the passive indexingmeans 7, 71, without using an active receiver, on a correspondingreference provided on said passive indexing means 7, 71 in order toalign the light beam that is projected by the emitter 6 relative to thispassive indexing means 7, 71, to then emit by means of said emitter 6 alight beam of light that is visible to an operator on the new spool 3that has been placed on the corresponding spindle of the spool-holdermeans 2 so as to allow the operator to move the spool-holder means 2laterally in order to match the side of the outside diameter of thespool 3 with the light beam that is projected by the emitter 6 and toalign and to prepare the start of the new web.

It should be noted here that the positioning of the emitter 6 is notdone systematically, this positioning not being necessary if the newspool has the same width as the spool that is ending.

According to one embodiment of the invention and as shown in FIG. 2 ofthe accompanying drawings, the passive indexing means 7 is composed of agraduated scale that is mounted on the group 5 for preparation of a newweb to be connected and for joining this web to a web that is ending.

It is likewise possible to implement passive indexing means 71 as shownin FIG. 4 of the accompanying drawings, in the form of a mountingsupport of the emitter 6, this support being provided with positioningreferences 71′ corresponding to references 700′ of a scale 700 forverifying the position of the new web of a group 5 for preparation of anew web to be connected and for joining this web to a web that isending. This support that forms the passive indexing means 71 can beimplemented in the form of a guide provided with positioning referencesby marks or again in the form of a guide provided with a means ofdigital display of the position.

By way of example, on a machine with transverse location-finding between0 and 650, the spool 3, for example with a width of 600 mm, can beloaded onto the spindle of the spool-holder means 2 at the corresponding600 mm reference provided as the reference 9, and the positioning of theemitter 6 will then be done on the corresponding 600 mm referenceprovided on the graduated scale that forms the passive indexing means 7(FIG. 2) that is mounted on the group 5 for preparation of a new web tobe connected and for joining this web to a web that is ending, and saidnew web is aligned laterally to match said light beam of visible lightthat has been emitted by the emitter 6.

Thus, the new web is perfectly aligned relative to the unwinding axis ofthe machine and with the web that is ending, such that a longitudinalfold cannot form after connection.

An identical result can be obtained by using the passive indexing means71 shown in FIG. 4 of the accompanying drawings. In such a case, it issufficient to position the emitter 6 on the mounting support that formsthe passive indexing means 71 on the positioning reference 71′corresponding to the reference 700′ of the scale 700 for verifying theposition of the new web of the group 5 for preparation of a new web tobe connected and for joining this web to a web that is ending.

The emitter 6 can emit a linear light beam or a light plane, or twointersecting light planes arranged, for example, at 90 degrees from oneanother, such that the resulting trace that is visible on the peripheryof the spool 3 is respectively a point, a line or a cross.

According to another characteristic of the invention, the emitter 6 canbe provided with a prism or mirrors for division of its light beam. Thisresults in that a part of the latter can be directed onto the peripheryof the spool 3 and in that the other part can be directed to the zonefor holding the start of the web in the group 5 for preparation of a newweb to be connected and for joining this web to a web that is ending, bypassing onto a graduated scale 7 (FIG. 2) located in this holding zone.

According to the invention, and as shown in FIG. 2 of the accompanyingdrawings, the device can comprise two emitters, one pointed toward thespool 3 and the other toward the holding zone of the group 5 forpreparation of a new web to be connected and for joining this web to aweb that is ending, these emitters being integral with one another.

According to another variant embodiment of the invention that is notshown in the accompanying drawings, it is likewise possible to use asingle emitter 6 with a beam that has an aperture angle such that itforms a light plane encompassing simultaneously the spool 3 and thepreparation zone of the group 5 for preparation of a new web to beconnected and for joining this web to a web that is ending.

The emitter 6 is preferably selected from among the family of laserdiodes, but any other highly convergent light source can be used.

The unrolling machine described relative to this invention issymmetrical to allow the new spool 3 to be located to the right or tothe left of the vertical center axis of the machine. Actually, when thespool 3 in the course of unwinding is placed to the right relative tothe vertical center axis of the machine, then a new spool 3 is placed tothe left of this axis and the end of the web of this new spool isprepared and placed in the holding zone located to the left of thisaxis, in the group 5 for preparation of a new web to be connected andfor joining this web to a web that is ending. Then, when the spool 3 inthe course of unrolling reaches the end of the web, the web that isending is. connected to the new web. To avoid stopping the machineplaced downstream from the unrolling machine during this changing of thespool, an accumulator or device 4 for storing the web located above theunrolling machine is used, which is designed to store a sufficientlength of the web before proceeding to the connection. For this purpose,the speed of the unrolling machine is temporarily increased relative tothe speed of the downstream machine, such that the excess length thathas been produced can be stored between the cylinders of theaccumulator. Then, the connection operation begins that requiresstopping of the web as it unwinds at the level of the connection zone.During this temporary stopping, the downstream machine is supplied withthe excess length of the web available in the accumulator 4 that isbeing progressively unwound. Once connection is completed, the new spoolthat has been placed to the left of the center axis is unrolled to thesite of the former one (FIG. 1). The former spool 3 that is located tothe right and that is empty or almost empty is removed and replaced by anew spool 3 that is located this time to the right. The machine operatorwill proceed to proper positioning of the new web of this spool 3 bymeans of the positioning device according to the invention, this simplyby visual monitoring of the position of the light beam of the visiblelight that has been emitted by the emitter 6, in combination with thepassive indexing means 7 or 71, without using a verification means suchas a sensor. Operations follow one another in this way by using the leftand right positioning devices of the machine in alternation.

This device according to the invention allows perfect angularpositioning between the web as it unwinds and the web in preparation.There can nevertheless be a slight defect of lateral alignment due to alateral defect on the spool in the course of unwinding.

In order to allow the lateral position of the web to be perfectlymaintained relative to the longitudinal axis of the unrolling machineduring unrolling of the spool 3, according to another characteristic ofthe invention, a lateral guide device 8 is added to the positioningdevice (FIG. 3).

This lateral guide device 8 is located downstream from the connectingzone of the group 5 for preparation of a new web to be connected and forjoining this web to a web that is ending and controls the lateralposition of the web in the course of unwinding relative to thelongitudinal axis of the machine.

According to one characteristic of the invention, the lateral guidedevice 8 advantageously has the form of a means for controlling thelateral position of the web relative to the longitudinal axis of themachine that notifies a central unit of the lateral position of the weband that is composed of a set of two optical cells 8′, 8″ located nextto one another near one edge of the web and spaced slightly laterallyrelative to the longitudinal axis of the machine. This device 8 can belocated to the left relative to the web when an observer is watching theunrolling machine frontally, the machine downstream being located in anextension of the web.

Thus, the correct position of the web is obtained when one of the cells8′, 8″ is activated. When the two cells 8′ and 8″ are activated at thesame time, the web is in the process of moving laterally to the left,viewed in the direction of unwinding, and then the spool 3 should bemoved in the corresponding unwinding by means of its spool-holdercarriage 2 toward the right in order to re-center the web as it unwinds.The movement of the spool-holder carriages 2 takes place transversely tothe longitudinal axis of the unrolling machine by means of electricmotors in the conventional manner and is not described in detail. Themovement of the spool-holder carriage takes place such that the web isautomatically re-centered as it unwinds.

Conversely, if neither of the two cells 8′, 8″ is activated, thisindicates that the web is in the course of moving to the right and thatthen the spool-holder carriage 2 should be moved to the left forre-centering the web. This type of control makes it possible to keep theedge of the web between the two cells.

By combining the lateral guide device 8 with the emitter 6, on the onehand it is possible to maintain an optimum lateral position of the webas it unwinds, and, on the other hand, to ensure that the position ofthe web of the new spool 3 will be in the alignment of the former weband that it will unroll without forming longitudinal folds.

Moreover, the invention ensures the quality of the webs as they unwind,due to the fact that the guide and positioning means are withoutcontact.

Of course, the invention is not limited to the embodiment described andshown in the accompanying drawings. Modifications remain possible,especially from the standpoint of the composition of various elements orby substitution of technical equivalents, without departing from theprotective scope of the invention.

1. Process for positioning webs and spools for purposes of connection onan unrolling machine, characterized in that it consists in marking, atthe level of the outside diameter of a spool (3), by means of an emitter(6) of a light beam of light visible to an operator and without using anactive receiver, the position to which the side of said spool (3) mustbe positioned relative to the longitudinal axis of the unrollingmachine.
 2. Process according to claim 1, wherein it consists in loadinga spool (3) onto the free spindle of a spool-holder means (2) to reach acorresponding reference (9), then optionally to laterally position theemitter (6) relative to the longitudinal axis of the machine, workingwith a passive indexing means (7, 71) provided on a group (5) forpreparation of a new web to be connected and for joining this web to aweb that is ending, without using an active receiver, on a correspondingreference provided on said passive indexing means (7, 71) in order toalign the light beam that is projected by the emitter (6) relative tothis passive indexing means (7, 71), to then emit, by means of saidemitter (6), a light beam of light visible to an operator on the newspool (3) that has been placed on the corresponding spindle of thespool-holder means (2) so as to allow the operator to move thespool-holder means (2) laterally in order to match the side of theoutside diameter of the spool (3) with the light beam projected by thelight source (6) and to align and to prepare the start of the new web.3. Process, according to claim 2, wherein the light beam emitted by theemitter (6) has the form of a linear light beam or light plane, or twointersecting light planes.
 4. Process, according to claim 2, whereinpart of the light beam is directed onto the periphery of the spool (3)and the other part is directed to the zone for holding the start of theweb in the group (5) for preparation of a new web to be connected andfor joining this web to a web that is ending, passing onto a graduatedscale (7 or 700) located in this holding zone and forming the passiveindexing means (7) or a scale (700) for verifying the position of thenew web.
 5. Device for implementing the process according to claim 1 ina machine for unrolling paper or cardboard spools for purposes offeeding a machine placed downstream such as a printing machine or thelike, this machine being essentially composed of a chassis (1) thatsupports means (2) of the spool-holder (3) that can move transversely tothe longitudinal axis of the machine, and optionally of a device (4) forstoring the web and by a group (5) for preparation of a new web to beconnected and for joining this web to a web that is ending, wherein itis composed essentially of at least one emitter (6) of a light beam inthe form of at least one linear beam or at least one light plane oflight that is visible to an operator, said emitter (6) working with apassive indexing means (7, 71), without using an active receiver. 6.Device, according to claim 5, wherein the passive indexing means (7) iscomposed of a graduated scale mounted on the group (5) for preparationof a new web to be connected and for joining this web to a web that isending.
 7. Device, according to claim 5, wherein the passive indexingmeans (71) has the form of a mounting support of the emitter (6), thissupport being provided with positioning references (71′) correspondingto references (700′) of a scale (700) for verifying the position of thenew web of the group (5) for preparation of a new web to be connectedand for joining this web to a web that is ending.
 8. Device, accordingto claim 7, wherein the support that forms the passive indexing means(71) is implemented in the form of a guide provided with positioningreferences by marks or again in the form of a guide provided with ameans for digital display of the position.
 9. Device according to claim5, wherein the emitter (6) is provided with a prism or mirrors fordivision of its light beam.
 10. Device according to claim 5, wherein itcomprises two emitters, one pointed toward the spool (3) and the othertoward the holding zone of the group (5) for preparation of a new web tobe connected and for joining this web to a web that is ending, theseemitters being integral with one another.
 11. Device according to claim5, wherein there is a single emitter (6) that has one beam that has anaperture angle such that it forms a light plane encompassingsimultaneously the spool (3) and the preparation zone of the group (5)for preparation of a new web to be connected and for joining this web toa web that is ending.
 12. Device according to claim 5, wherein theemitter (6) is preferably selected from among the family of laserdiodes.
 13. Device according to claim 5, wherein the emitter (6) is ofthe highly convergent beam type.
 14. Device according to claim 5,wherein a lateral guide device (8) is added to it.
 15. Device accordingto claim 14, wherein the lateral guide device (8) is located downstreamfrom the connecting zone of the group (5) for preparation of a new webto be connected and for joining this web to a web that is ending andcontrols the lateral position of the web in the course of unwindingrelative to the longitudinal axis of the machine.
 16. Device accordingto claim 14, wherein the lateral guide device (8) has the form of ameans for controlling the lateral position of the web relative to thelongitudinal axis of the machine that notifies a central unit of thelateral position of the web and that is composed of a group of twooptical cells (8′, 8″) located next to one another near one edge of theweb and slightly spaced laterally relative to the longitudinal axis ofthe machine.
 17. Device according to claim 15, wherein the lateral guidedevice (8) has the form of a means for controlling the lateral positionof the web relative to the longitudinal axis of the machine thatnotifies a central unit of the lateral position of the web and that iscomposed of a group of two optical cells (8′, 8″) located next to oneanother near one edge of the web and slightly spaced laterally relativeto the longitudinal axis of the machine.
 18. Device according to claim6, wherein the emitter (6) is preferably selected from among the familyof laser diodes.
 19. Device according to claim 6, wherein the emitter(6) is of the highly convergent beam type.
 20. Device according to claim6, wherein a lateral guide device (8) is added to it.